Features: * Suitable for Car Video & Audio Devices, such as headrest DVD players. * Ultralight design for long time comfortable wearing, perfect enjoyment. * IR dual-channel wireless headphone function. Operating distance is up to 10 meters. * Automatically mute and auto power off if no signal is received about 5 minutes. * Built-in 40mm mylar speaker for audiophile grade sound quality. * Works with smart phones, tablet PC, MP3 devices via a 3.5mm audio cable (not included). Note: When use the device as wired headphone, volume knob on the headphone cannot be used, and you can only adjust volume on your audio device. Specifications: Channel: Dual Mode: Stereo Carrier Frequency: a) A channel: 2.8MHz for right channel; 2.3MHz for left channel b) B channel: 3.8MHz for right channel; 3.2MHz for left channel Operating Distance: up to 12 meters Frequency Response: 60Hz-6000Hz Sensitivity: -88dBm±3dB Impedance: 32Ω S/N Ratio: ≥50dB Channel separation: >35dB Distortion: <1% Power Supply: 2 * AAA Batteries (Not Included) Main Item Size: 17.6 * 15.3 * 6.4cm / 6.92 * 6.02 * 2.51in Main Item Weight: 123g / 4.34oz Package Size: 19.9 * 15.4 * 4.2cm / 7.83 * 6.06 * 1.65in Package Weight: 180g / 6.36oz Package List: 1 * IR Infrared Wireless Stereo Car Headphone 1 * English User Manual